To make a wet screed for the floor is not difficult, but rather laborious. In this review, we consider in detail all the features of this work. The first question to be decided is what is a wet floor screed? Under it today refers to the upper layer of material laid on top of the floor. As a rule, it is used to level the floors in different rooms, and also makes the surface level for subsequent laying of the finish coating.
Features
Let's dwell on this in more detail. How is a wet floor screed device implemented? This type of screed is laid on any types of floors, including on bare ground. Installation of a wet screed can be carried out on top of a layer of thermal and waterproofing. The mount is suitable for installing any kind of finishing materials.
Wet floor screed has a number of disadvantages. These include:
- heavy weight;
- long solidification time - up to 90 days;
- complete drying time - from six months;
- coating strength depends on adherence to technology and quality of materials.
However, all these disadvantages of wet screed more than overlap with the result.
There are two options for arranging the mount. In the first case, it is made as an independent part lying on the floor. In the second case, it is necessary to achieve strong adhesion of the base and screed. If you plan to install underfloor heating at home, then it is better to use the first option. When the temperature changes, the stove should be able to "breathe".
Before filling, a damping tape is installed around the perimeter of the room, and then a heat-insulating layer. For the screed to be strong enough, it must have a significant thickness. Otherwise, its service life will be small. The thickness of the wet screed underfloor heating is usually 8-10 cm.
Manufacturing steps
Let's dwell on this aspect in more detail. How is a wet floor screed done? The technology includes the following steps:
- Foundation preparation.
- Installation of beacons.
- Preparation of the solution and its filling.
- Finishing screeds.
If you decide to start arranging a wet screed yourself, you need to figure out how each stage of installation is carried out.
Foundation preparation
Before filling the screed, it is recommended to carefully sweep the base. Chunks of mortar that have dried to the surface should also be removed. For laying on a layer of thermal insulation this will be enough. If you need the screed to adhere well to the base, the surface should be well treated: thoroughly sweep with a damp broom, prime with acrylic-based compound, and treat the concrete with contact. Be sure to check the floor for cracks and holes, otherwise the mortar may leak to the neighbors.
We install beacons
Why is this necessary? To wet floor screed turned smooth, it is required to install beacons. On how carefully you will perform the work at this stage, depends on the horizontal surface, resulting in the end. Galvanized profiles are best suited for beacons. They have the required stiffness. You can also use ordinary plaster beacons, the thickness of which is only 9 mm. Experienced builders use alabaster for their installation. This material quickly hardens. But you can use simple gypsum plaster. It is convenient, flexible, and you can install beacons in it with an accuracy of a millimeter.
Pouring screed
So what do you need to know about this? After completing the preparatory phase, it is worth starting to pour the wet screed. The procedure can be greatly simplified if you establish a kind of conveyor for the preparation of a cement mixture. It should have a uniform composition and consistency. Excess water in this case is useless. You should start from the far wall of the room and gradually move to the door. The surface of the screed should be leveled according to the level of the beacons using the rule. It will begin to exfoliate and release water. No puddles should remain on the surface of the screed. Get ready for the dreary and dirty work.
Debugging
After pouring the screed, give it a day to harden. At this point, the beacons are retrieved. Cement mortar is also poured into the recesses remaining after them. Further work with the screed will depend on the type of finish coating placed on it. If it is a tile, then the work can be completed. Some coatings require a perfectly flat surface. In this case, the screed will need to be additionally wiped with a grater and fresh mortar.
When can I start walking on a freshly laid screed? After a day, they recommend trying to take the first steps, but for complete hardening, it is desirable to withstand the coating for four weeks at normal air temperature. Only then can you start laying the topcoat. It is worth noting that, at lower temperatures, solidification will go more slowly. How long does a wet floor screed dry on a balcony? It depends on the temperature and humidity of the environment.
Drying the hood is a different process. The thicker the coating layer, the longer it will dry. Low temperatures and high humidity can significantly slow down drying. If the residual moisture does not play a special role for laying ceramic tiles, then this is a very significant factor for parquet.
Minimum tool kit
How to make a wet floor screed with your own hands? For work you will need:
- primer brushes;
- 20 liter buckets for solution preparation;
- electric mixer for concrete;
- level;
- spatulas;
- the rule.
If we are talking about pouring screeds in a small area, for example, in a bathroom, then you can do it yourself. A large area alone cannot be filled. Wet floor screed in a panel house apartment can turn into a whole problem if you do not prepare. It will be necessary to find and repair all targets and cracks in the overlap. It is not always possible to do this, so it will be easier to simply lay the floor with a layer of polyethylene. The edges of the film are raised by 20-30 cm. In this case, not a drop of solution will leak to the neighbors.
Materials
So what do you need to know about this? The quality of the resulting coating will depend on the materials used. A wet screed for a warm floor in an apartment can be prepared from a mixture of sand and cement. Particular attention should be paid to the sand used. It should not contain clay impurities. Cement quality is more difficult to verify. It is best to use ready-made cement-sand mixtures. You can find detailed cooking instructions on the packaging.
As a filler, crushed expanded clay or a powder can be added to the mixture. This will reduce its consumption. In addition, expanded clay will easily take away excess water, and when hardened, gives it away. Such a screed with bedding practically does not crack. Try to knead carefully each portion of the mixture. With careless mixing, the strength of the material is significantly reduced. If you doubt the quality of the dry mix for screed, you can add 2-3 handfuls of Portland cement to a serving.
Semi-dry screed
What is its feature? The composition in this case will be identical to the wet screed. The difference is only in the level of moisture content. Based on the name, we can conclude that in this case, half the amount of water is required.
As for the technology of laying semi-dry screed, it is also slightly different. The composition is evenly distributed over the designated area. It is laid in several layers, each of which is properly rammed. When the screed reaches the desired level, the excess can be removed using the rule. After 2-3 hours it is allowed to walk on the surface. At this time, finish leveling and surface treatment with a metallic brush is performed.
The choice of type of screed must be done, taking into account their features. The semi-dry method has a number of distinctive characteristics:
- high density;
- lack of need for reinforcing;
- ease of installation;
- shrinkage during drying;
- the ability to install the finish coating immediately after drying and hardening of the surface.
Semi-dry or wet floor screed have one significant drawback - this is the weight of the finished structure. It can create a serious load on the floors, and this is definitely worth considering.
Dry screed
Let's look at this aspect in more detail. Dry or wet floor screed - which is better? This question is of interest to many owners of private houses and city apartments today. The technology for installing a dry screed differs significantly from wet and semi-dry. In this case, a loose heat insulator and sheet materials are used. We give an approximate order of work:
- Wooden slats or logs are laid out on a concrete base or rough screed.
- After leveling the lag in the horizontal plane, the elements are fixed. For this purpose, it is best to use metal corners intended for the assembly of the roof.
- Expanded clay is poured into the space between the lags.
- Sheets of plywood, OSB or chipboard are laid on the bedding. They are attached to the rails using self-tapping screws, and are fastened to each other using special glue.
Expanded clay is a lightweight, porous material from burnt clay. It has excellent sound insulation and will retain heat well in the room. In addition, expanded clay is a "breathing" material. In the room where such a screed is used, there will always be an excellent microclimate. The screed will not mold or rust. Experts also note the fire-resistant properties of expanded clay.
Compared to wet and semi-dry screed, dry screed is much easier to install. This will help reduce the load on the floor or foundation. In addition, this technology will cost you much cheaper. The advantages of a dry screed can also include:
- Installation speed: all work on arranging the screed can be done in one day with your own hands.
- The materials used provide good heat and sound insulation properties.
- Dry screed is considered the most appropriate option when planning the installation of a warm floor system. In the event of a malfunction, the structure is easily disassembled.
- Using such a screed, you can even the floors with large differences in height. The layer of the mixture can have any thickness, because it will still remain light.
- On top of a dry screed, any finishing flooring can be laid.
- Such floors can significantly save on heating in the cold season.
Dry screed also has its drawbacks. These include the possible formation of dust during strong impacts on the base. Therefore, if you have people with asthma in your family, this option is not recommended. If water enters the coating, problems can also occur. The top layer of the coating will have to be disassembled in order to dry expanded clay. This can be a nuisance. Therefore, it is not recommended to do a dry floor screed in rooms with high humidity: in the bathroom, kitchen and toilet.
Which one to choose?
Now that we have examined the features of the technology of laying all types, we can try to answer the fundamental question: which floor screed is better - dry or wet? It is impossible to answer unequivocally. Each view is suitable for certain rooms. For example, it is recommended to use dry screeds in the presence of wooden floors in those rooms where the possibility of the appearance of water and high humidity is excluded. Wet floor screed can be used in the kitchen, bathroom or toilet. Also, such a screed is suitable for arranging a garage. A self-leveling mixture is best suited for laying flooring in a living room.
Conclusion
In this review, we examined in detail what are the different types of screeds for the floor. There are three types in total: wet, semi-dry and dry. Wet floor screed is the most troublesome thing. The technology of its installation is quite complex and takes a lot of time. The quality of the resulting coating depends on many factors: surface preparation, quality of the composition used, and ambient temperature. In addition, it is quite difficult to independently carry out installation work on such a screed.
Semi-dry screed, as the name implies, differs from wet in terms of moisture content in the composition. The installation procedure here will also be slightly different. For example, a semi-dry screed requires careful tamping. Such a coating dries much faster.
The simplest option is laying dry screed. It provides good sound and heat insulation characteristics. However, for rooms with a high level of humidity, such a screed is better not to use.